Aerial lift interlocked with fall-protection safety apparatus

Abstract

An aerial lift that is interlocked with a fall-protection safety apparatus and may be further interlocked with at least one additional safety apparatus. The aerial lift is equipped with a monitoring system that is configured to detect whether a connector of a safety line of the fall-protection apparatus appears to be connected to a safety harness of a user of the aerial lift.

What is claimed is: 
     
       1. An aerial lift comprising:
 a fall-protection safety apparatus installed on the aerial lift and comprising a safety line with a distal end comprising a connector configured to be connected to a safety harness worn by a user of the aerial lift, the aerial lift comprising a fall-protection monitoring system configured to determine whether the connector of the safety line appears to be connected to the safety harness of the user and the aerial lift comprising at least one additional safety apparatus in addition to the fall-protection safety apparatus;
 wherein the aerial lift is interlocked with the fall-protection safety apparatus and with the at least one additional safety apparatus of the aerial lift so that in order for at least a vertical-motion function of the aerial lift to be enabled, control circuitry of the aerial lift must receive at least one first positive signal from the fall-protection monitoring system indicating at least that the connector of the safety line appears to be connected to the safety harness of the user; and, the control circuitry of the aerial lift must receive at least one additional positive signal from the at least one additional safety apparatus of the aerial lift indicating that the at least one additional safety apparatus of the aerial lift is in a ready condition; 
 wherein the fall-protection monitoring system comprises a base unit and comprises at least one sensor module mounted on the connector and configured to sense whether the connector appears to be connected to the safety harness and to transmit connector status information to the base unit that is indicative of whether the connector appears to be connected to the safety harness; and 
 wherein the base unit is configured to receive the connector status information from the at least one sensor module and to send the at least one first positive signal to the control circuitry of the aerial lift if the connector status information received from the at least one sensor module indicates that the connector appears to be connected to the harness and to not send any first positive signal to the control circuitry of the aerial lift if the connector status information received from the at least one sensor module indicates that the connector does not appear to be connected to the harness. 
 
 
     
     
       2. The aerial lift of  claim 1  wherein the at least one additional safety apparatus of the aerial lift comprises an operator presence control (OPC) switch that is configured so that when the OPC switch is in a condition indicative of active control of the aerial lift by the user of the lift, the OPC switch sends a primary additional positive signal indicating that the OPC switch is in a ready condition. 
     
     
       3. The aerial lift of  claim 2  wherein the at least one additional safety apparatus of the aerial lift further comprises a safety gate apparatus comprising at least a first safety gate that is configured to be moved between a stowed position and a protective position;
 wherein when the first safety gate is in its protective position it is disposed generally above a first lateral edge of the operator-support platform, 
 wherein the safety gate apparatus is configured to send a secondary additional positive signal that the safety gate apparatus is in a ready condition when at least the first safety gate is in its protective position, 
 and wherein in order for at least the vertical-motion function of the aerial lift to be enabled, the at least one first positive signal must be received from the fall-protection monitoring system, the primary additional positive signal must be received from the OPC switch, and the secondary additional positive signal must be received from the safety gate apparatus. 
 
     
     
       4. The aerial lift of  claim 2  wherein the at least one additional safety apparatus of the aerial lift further comprises an operator authorization safety apparatus, and wherein in order for at least the vertical-motion function of the aerial lift to be enabled, the at least one first positive signal must be received from the fall-protection monitoring system, the primary additional positive signal must be received from the OPC switch, and a tertiary additional positive signal must be received from the operator authorization safety apparatus. 
     
     
       5. The aerial lift of  claim 1  wherein the fall-protection safety apparatus comprises a self-retracting lifeline (SRL) comprising a housing, with a proximal end of the safety line of the fall-protection safety apparatus being connected to a drum that is within the housing of the SRL and is rotatably connected to the housing of the SRL and with the safety line being extendable out of the housing and retractable into the housing; and, wherein the housing of the SRL is attached to an overhead guard of the aerial lift, the overhead guard of the aerial lift being positioned generally vertically overhead of an operator-support platform of the aerial lift. 
     
     
       6. The aerial lift of  claim 1  wherein the fall-protection monitoring system is configured to perform at least one self-check of at least one component of the fall-protection monitoring system and wherein the base unit is configured so that if the self-check indicates that the at least one component of the fall-protection monitoring system appears to be in a ready condition, the base unit will send at least one supplemental first positive signal, and wherein the control circuitry of the aerial lift is configured so that it must receive the at least one supplemental first positive signal from the fall-protection monitoring system in order for at least the vertical-motion function of the aerial lift to be enabled. 
     
     
       7. The aerial lift of  claim 6  wherein the fall-protection monitoring system is configured to perform self-checks of first, second and third components of the fall-protection monitoring system and wherein the base unit is configured so that if the self-checks indicate that the first, second and third components of the fall-protection monitoring system all appear to be in a ready condition, the base unit will send three supplemental first positive signals, and wherein the control circuitry of the aerial lift is configured so that it must receive all three supplemental first positive signals from the fall-protection monitoring system for at least the vertical-motion function of the aerial lift to be enabled;
 and, wherein the first self-checked component of the fall-protection monitoring system is the sensor module, the second self-checked component of the fall-protection monitoring system is the base unit, and the third self-checked component of the fall-protection monitoring system is at least one internal battery that powers at least the sensor module. 
 
     
     
       8. The aerial lift of  claim 7  wherein the first self-checked component of the fall-protection monitoring system is the sensor module, the second self-checked component of the fall-protection monitoring system is the base unit, and the third self-checked component of the fall-protection monitoring system is the at least one internal battery that powers at least the sensor module. 
     
     
       9. The aerial lift of  claim 1  wherein the fall-protection monitoring system is configured so that if the base unit of the fall-protection monitoring system receives connector status information from the at least one sensor module indicating that the connector appears to be connected to the harness, the fall-protection monitoring system will broadcast at least one Ready notification indicating that the connector appears to be connected to the harness, in addition to sending the at least one first positive signal to the control circuitry of the aerial lift. 
     
     
       10. The aerial lift of  claim 1  wherein the control circuitry of the aerial lift is configured to receive the at least one first positive signal from the base unit of the fall-protection monitoring system through a wired connection with the base unit, the wired connection being configured so that the base unit of the fall-protection monitoring system is galvanically isolated from the control circuitry of the aerial lift. 
     
     
       11. The aerial lift of  claim 1  wherein the aerial lift is configured so that in the absence of the at least one first positive signal from the fall-protection monitoring system and the at least one additional positive signal from the at least one additional safety apparatus, the aerial lift is unable to elevate from a first, lowered position but is still able to descend from an elevated position. 
     
     
       12. The aerial lift of  claim 1  wherein the aerial lift is configured so that in the absence of the at least one first positive signal from the fall-protection monitoring system and the at least one additional positive signal from the at least one additional safety apparatus of the aerial lift, the aerial lift is unable to elevate from a first, lowered position, beyond a predetermined height that is 4.0 feet or less above the first, lowered position; and, wherein the aerial lift is further configured so that upon receiving of the at least one first positive signal from the fall-protection monitoring system and the at least one additional positive signal from the at least one additional safety apparatus, the aerial lift is able to elevate beyond the predetermined height above the first, lowered position. 
     
     
       13. The aerial lift of  claim 1 , wherein the aerial lift is an order picker. 
     
     
       14. A method of controlling the operation of the aerial lift of  claim 1 , the method comprising:
 upon receiving at least one first positive signal from the fall-protection monitoring system indicating at least that the connector of the safety line of the fall-protection safety apparatus appears to be connected to the fall-protection safety harness of the user and receiving at least one additional positive signal from at least one additional safety apparatus of the aerial lift, enabling at least a vertical-motion function of the aerial lift; 
 and, upon the at least one first positive signal and/or the at least one additional positive signal not being received, or ceasing to be received, disabling at least the vertical-motion function of the aerial lift. 
 
     
     
       15. The aerial lift of  claim 1  wherein the sensor module is located on the connector of the fall-protection safety apparatus, wherein the base unit is co-located with the sensor module on the connector of the fall-protection safety apparatus with the sensor module sending the connector status information to the base unit through a wired connection; and, wherein the base unit is configured to wirelessly send the first positive signal to the control circuitry of the aerial lift. 
     
     
       16. The aerial lift of  claim 15  wherein the connector of the fall-protection safety apparatus comprises a gated hook and wherein the sensor module is installed in a housing fitted onto at least a portion of a main body of the gated hook. 
     
     
       17. The aerial lift of  claim 1  wherein the sensor module comprises a sensor that comprises an RFID reader configured to detect the presence of an RFID tag disposed at or on a D-ring of the safety harness worn by the user, the fall-protection monitoring system being configured so that detection of the RFID tag by the RFID reader provides the indication that the connector of the safety line of the fall-protection safety apparatus appears to be connected to the safety harness, which indication causes the fall-protection monitoring system to send the at least one first positive signal to the control circuitry of the aerial lift. 
     
     
       18. The aerial lift of  claim 1  wherein the fall-protection safety apparatus comprises a self-retracting lifeline (SRL) comprising a housing, with a proximal end of the safety line of the fall-protection safety apparatus being attached to a drum that is within the housing of the SRL and is rotatably connected to the housing of the SRL, with the safety line being extendable out of the housing and retractable into the housing, with the connector of the fall-protection safety apparatus being attached to a distal end of the safety line, and with the housing of the SRL being secured to an anchorage of the aerial lift. 
     
     
       19. The aerial lift of  claim 1  wherein the aerial lift is configured so that in the absence of the at least one first positive signal from the fall-protection monitoring system and the at least one additional positive signal from the at least one additional safety apparatus of the aerial lift, the aerial lift is unable to elevate from a first, lowered position but is still able to descend from an elevated position. 
     
     
       20. The aerial lift of  claim 1  wherein the aerial lift is configured so that in the absence of the at least one first positive signal from the fall-protection monitoring system and the at least one additional positive signal from the at least one additional safety apparatus of the aerial lift, the aerial lift is unable to elevate from a first, lowered position beyond a predetermined height that is 4.0 feet or less above the first, lowered position; and, wherein the aerial lift is further configured so that upon receiving of the at least one first positive signal and the at least one supplemental first positive signal from the fall-protection monitoring system, the aerial lift is able to elevate beyond the predetermined height above the first, lowered position. 
     
     
       21. The aerial lift of  claim 1  wherein the fall-protection monitoring system of the fall-protection safety apparatus and the control circuitry of the aerial lift are configured so that there is two-way communication therebetween and so that the control circuitry of the aerial lift sends information to the fall-protection monitoring system regarding the elevation of the aerial lift. 
     
     
       22. The aerial lift of  claim 1  wherein the connector of the fall-protection safety apparatus comprises a gated hook with the sensor module being installed in a housing fitted onto at least a portion of a main body of the gated hook, and wherein the safety line of the fall-protection safety apparatus comprises a shock absorber. 
     
     
       23. The aerial lift of  claim 1  comprising a fall-protection system that comprises the fall-protection safety apparatus, the fall-protection monitoring system, and the safety harness worn by the user of the aerial lift, the connector of the safety line of the fall-protection apparatus being connected to the safety harness worn by the user and a housing of the fall-protection safety apparatus being secured to an anchorage of the aerial lift. 
     
     
       24. The aerial lift of  claim 23  wherein the connector of the safety line of the fall-protection safety apparatus comprises a gated hook and wherein the safety harness comprises at least one D-ring with the gated hook connected thereto.